kt,
Is this a new placed controller by a contractor or was it installed by you? What is the model number? How many zones? Does the zone start with good pressure and after a minute of time then the zone suddenly stops. Are you willing to troubleshoot yourself or have a irrigation specialist do it? What is the fault error that you get from the controller? Seems to me to be three possibility. A system pressure/valve, a controller or an electrical connection problem. JMHO Aloha